System and method for estimating an amount of a blood component in a volume of fluid

ABSTRACT

System and methods for analyzing the contents of a fluid canister are provided for use in healthcare settings. The system includes optical and weight sensors to analyze the canister contents.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of prior U.S. application Ser. No.15/389,365, filed on Dec. 22, 2016, and claims priority to U.S.Provisional Patent Application No. 62/387,234, filed on Dec. 23, 2015,both of which are hereby incorporated by reference in their entirety.These applications are also related to U.S. patent application Ser. No.13/544,664, filed on Jul. 9, 2012, and issued as U.S. Pat. No. 9,652,655on May 16, 2017, and to U.S. patent application Ser. No. 13/738,919,filed on Jan. 10, 2013, issued as U.S. Pat. No. 8,983,167 on Mar. 17,2015, both of which are hereby incorporated by reference in theirentirety.

TECHNICAL FIELD

This invention relates generally to the field of blood loss managementand more specifically to a new and useful system and method forestimating an amount of a blood component in a volume of fluid in thefield of blood loss management.

SUMMARY

In one example, a system for assessing a fluid canister is provided,comprising a mounting structure with a canister recess and an imagingdevice recess, an inter recess wall between the canister recess and theimaging device recess, a scale coupled to the mounting structure andconfigured with at least one measurement element in communication withthe canister recess, and a scale communication module configured totransmit weight information from the scale to a computing device. Themeasurement element may comprise a piezoelectric element. The imagingdevice recess may comprise a data interface in wired communication withthe communication module. The system may further comprise a firstaperture located in the inter-recess inter-recess wall. The firstaperture may include a window and seal between the window and theinter-recess wall. The system may further comprise a second aperturelocated in the inter-recess wall. The inter-recess wall may comprise acurved portion with a concave surface facing the canister recess. Theinter-recess wall may further comprise a flat portion facing the imagingdevice recess. The canister recess may comprise a movable surface. Thesystem may further comprise a fluid canister configured to removablyreside in the canister recess, and wherein the reflective insert may beconfigured to reside inside the fluid canister. The system may furthercomprise a reflective insert configured to reside within the fluidcanister. The inter-recess wall may comprise a first aperture located ata vertical height corresponding to the reflective insert when placed ata bottom of the fluid canister when the fluid canister may be fullyseated in the canister recess. The fluid canister may have afrusto-conical shape. The inter-recess wall has a vertical anglematching a frusto-conical angle of the fluid canister. The system mayfurther comprise an imaging device configured to be removably insertedinto the imaging device recess. The imaging device may be a computingdevice comprising an imaging assembly configured to acquire canisterimages from canister located in the canister recess and a processorconfigured to receive weight information from the communication module.The processor may be further configured to acquire a canister image withthe imaging assembly upon detecting a weight change using the weightinformation. The computing device may further comprise a computingcommunication module configured to transmit the canister images andweight information from the computing device. The fluid canister maycomprise an inlet and an outlet, wherein the outlet may be configured tobe coupled to a vacuum source. The computing device may be configured toacquire canister images at the same acquisition rate that the processormay be configured to acquire weight information. The acquisition ratemay be in the range of about one acquisition every 1 to 5 seconds.

In another example, a method of assessing a fluid canister is provided,comprising detecting the weight a fluid canister attached to a vacuumsystem, generating an image of the fluid canister, and determining ahemoglobin value of the fluid canister using the image. The imaging maybe initiated upon detecting a change in the weight of the fluidcanister. The method may further comprise modifying the hemoglobin valueusing the weight. The method may further comprise draining the fluidcanister, and setting a tare weight of the fluid canister after drainingthe fluid canister.

In still another example, a blood monitoring system is provided,comprising a canister, a mount, a weighing scale, an imaging system, anda processor, wherein the canister defines an internal volume andcomprises a translucent section. The blood monitoring system may furthercomprise a reflective insert arranged within the internal volume andadjacent and offset from the translucent section. The mount may beconfigured to engage an exterior surface of the canister. The mount maydefine a first window configured to seal over the exterior surface ofthe canister proximal the translucent section. The mount may furtherdefine a second window adjacent the first window and configured to sealover the exterior surface of the canister proximal the translucentsection. The first window may be substantially optically isolated fromthe second window. The weighing scale may be coupled to the mount andmay be configured to output a signal corresponding to a weight ofcontents in the canister. The imaging system may comprise an opticalemitter aligned with the first window and configured to illuminate thereflective insert through the translucent section of the canister. Theimaging system may further comprise a camera aligned with the secondwindow. The processor may be configured to transform an image capturedby the camera into an estimated concentration of a blood component in afluid within the canister and to estimate an amount of the bloodcomponent in the canister based on the estimated concentration of theblood component and an output of the weighing scale.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic representation of a canister assessment system;

FIGS. 2A and 2B are schematic representations of one variation of asystem described herein;

FIG. 3 is a schematic representation of a method for assessing acanister;

FIG. 4A to 4C are schematic examples of a fluid canister with anintegrally formed reflective surface;

FIG. 5A is an example of a fluid canister with a sump pickup; FIGS. 5Band 5C are examples of fluid canisters with a sump pickup and integratedfloat sensor and fluid level sensor, respectively; and

FIG. 6A is a side cross-sectional view of a fluid canister with amagnetic agitator; FIG. 6B is a superior schematic view of thereflective insert in FIG. 6A; FIG. 6C is a side cross-sectional view ofanother fluid canister with a magnetic agitator; FIG. 6D is a issuperior schematic view of the reflective insert in FIG. 6C; FIG. 6E isa side cross-sectional view of another fluid canister with a mechanicalagitator.

DESCRIPTION OF THE EMBODIMENTS

The following description of embodiments of the invention is notintended to limit the invention to these embodiments but rather toenable a person skilled in the art to make and use this invention.Variations, configurations, implementations, example implementations,and examples described herein are optional and are not exclusive to thevariations, configurations, implementations, example implementations,and examples they describe. The invention described herein can includeany and all permutations of these variations, configurations,implementations, example implementations, and examples.

1. System

Generally, the system 100 includes a canister 102 configured to collectand hold fluid, an optical emitter 128 that illuminates fluid in thecanister 102, a camera 130 that captures images of illuminated fluid,and a processor 132 that transforms color values contained in imagescaptured by the camera 130 into estimations of a quality of fluidcontained in the canister 102, such as a concentration of totalhemoglobin, free hemoglobin, whole red blood cells, or whole blood, etc.in the fluid in the canister 102. The system also includes a weighingscale 106, and the system 100 can generate an estimation of a mass orvolume of one or more blood components in the canister by merging anoutput of the weighing scale 106 with a blood component concentrationthus estimated from color values in an image of the canister 102. Forexample, an estimate of the total hemoglobin content of the fluid in thecanister may be calculated using the combination of the estimatedconcentration and volume of a blood component generated from the imageand weight information from the scale, respectively.

In one particular example, as shown in FIG. 1, a system 100 forestimating an amount of a blood component in a volume of fluid includesa canister 102, a mount 104, a weighing scale 106, an imaging system108, and a processor 132. The canister 102 defines an internal volume112 and a translucent section 114 or wall, and may include a reflectiveinsert 116 arranged within the internal volume 112 and adjacent andoffset from the translucent section 114. The mount 104 is configured toengage an exterior surface 118 of the canister 102, and may comprise afirst window 120 with a first seal 122 a/b configured to seal over theexterior surface 118 of the canister 102 proximal the translucentsection 114, and may further comprise a second window 124 adjacent thefirst window 120 and configured to seal over the exterior surface 118 ofthe canister 102 proximal the translucent section 114, wherein the firstwindow 120 is substantially optically isolated from the second window124, by the first seal 122 a/b. The weighing scale 106 is coupled to themount 104 and is configured to output a signal corresponding to a weightof contents in the canister 102. The imaging system 126 includes anoptical emitter 128 aligned with the first window 120 and configured toilluminate the reflective insert 116 through the translucent section 114of the canister 102, and also includes a camera 130 aligned with thesecond window. The imaging system components may be provided on acomputing device 131. The processor 132 is in communication with theimaging system of the computing device 131 and is configured totransform an image captured by the camera 130 into an estimatedconcentration of a blood component in a fluid within the canister 102and to estimate an amount or volume of the blood component in thecanister 102 based on the estimated concentration of the blood componentand an output of the weighing scale 106. In some examples, the processor132 may be located in a remote computing system or cloud-based system,but in other examples, the processor 132 may be located or incorporatedinto the computing device 131.

In other variations, the scale 106 may also be used to detect otheractivity relating to the canister 102 and/or the fluid in the canister102. For example, removal of the canister 102 may be detected so thatthe processor 132 can store the last or final concentration and volumeinformation from the removed canister 102 and reset any counter(s) orregister(s) for measuring any new canister.

1.1 Applications

The system 100 can be integrated into a surgical suction system withinan operating room, surgical or procedure suite, emergency room, medicalclinic, or other medical or health-related setting. In particular thesystem can interface with a primary canister and a suction wand in asurgical suction system to intermittently accumulate fluid collectedwith the suction wand, to capture an image of this fluid, to transformthis image into an estimation of a quality of the fluid, and to thenrelease its contents into the primary canister. For example, a vacuumpump 134 and regulator 136 coupled to a primary canister 138 can drawvacuum on the primary canister 138; the primary canister 138 can befluidly coupled to the (intermediate) canister 102 of the system 100,and the suction wand 140 can be fluidly coupled to the (intermediate)canister 102 of the system 100 such that, when the vacuum pump 134 drawsa vacuum on the primary canister 138, vacuum is communicated to thesuction wand 140 via the (intermediate) canister 102 of the system 100.A nurse, anesthesiologist, surgeon, or other operator can thusmanipulate the suction wand 140 to collect fluids from within and arounda patient during a surgery and to dispense these fluids into the(intermediate) canister 102. The system 100 repeatedly captures andprocesses images of fluid in the canister 102 and samples the weighingscale 106 to generate updated fluid quality and quantity estimationsthroughout operations or procedures. In this example, once the(intermediate) canister 102 is full, its contents can be dispensed intothe primary canister 138 for holding; the (intermediate) canister 102can then be refilled via the suction wand 140 and its contents analyzedoptically and/or by weight.

The system 100 can therefore be implemented in conjunction with asurgical wand and/or a primary (suction) canister within a surgical orother medical, clinical, or hospital setting to collect and imagediscrete volumes of blood and other bodily fluids. Components in thesystem that contact hazardous waste (e.g., blood, mucus, urine, etc.)can be disposable, and sensor and processing components of the systemcan be reusable. For example, the canister and the reflective insert canbe used during a single operation or surgery and then disposed of, andthe mount, weighing scale, imaging system, and processor can installedon multiple canisters across multiple surgeries over time to opticallyanalyze qualities of fluids captured in these one-time-use canisters.

In other examples, the suction system may be attached to other vacuumsystems, such as a negative pressure wound therapy system or a chesttube system, or an indwelling surgical draining tube, for assessing theamount and/or type of fluid loss or accumulation at those anatomicalsites.

1.2 Canister

As noted previously, the intermediate canister 102 defines an internalvolume 112 and a translucent section 114 or sidewall; and may include areflective insert 116 configured to be inserted or arranged within theinternal volume 112 and adjacent and offset from the translucent section114. Generally, the canister 102 defines a vessel configured to collectfluid over time, includes a translucent or transparent material throughwhich the imaging system 126 can illuminate contents of the vessel andcapture images of contents of the vessel, and may include a reflectiveinsert 116 (or reflective surface) that reflects and spreads lightoutput from the imaging system 126 across a local volume of fluid to beimaged. The reflective insert 116 may cooperate with the wall 142 of thecanister 102 to constrain a local volume of fluid in the canister 102 toa relatively shallow depth such that the imaging system 126 can capturecolor data through the full depth of this local volume of fluid(substantially) despite a concentration of red blood cells in thecanister that may progressively block light transmission at greaterdepths. In some variations, the reflective insert 116 and the canister102 may comprise recesses 195 and projections 197 configured to set therotational orientation of the insert 116 and the canister 102.

In one implementation, the canister has a frusto-conical shape and iscomprised of a substantially transparent polymer (e.g., polyethyleneterephthalate, polymethyl methacrylate, polycarbonate, cellulose acetatebutyrate) and may be configured to hold 3,000 milliliters of fluid. Inother examples, the canister may have a capacity in the range of about500 ml to 10,000 ml, or about 1,000 ml to about 5,000 ml, or about 1,000ml to 3,000 ml. The reflective insert may be comprised of any suitablematerial, for example, a polymer (e.g., white nylon, polycarbonate,polyethylene, polymethyl methacrylate) structure configured to sit in,or couple to, the bottom of the canister. In this implementation, thecanister can include an engagement feature in its base or in the wall ofthe vessel proximal its base and configured to retain the reflectiveinsert. In other variations, the canister may comprise a polygonalshape, a cylindrical shape, or other shape, including one with at leastone planar side surface or wall.

Alternatively, as depicted in FIG. 4A, the canister 400 may include acolumn 402 within the internal volume 404 of the canister 400 andextending upwardly from the base 406 of the frusto-conical vessel,offset inwardly from the interior wall 408 of the frusto-conical vessel,and backed or covered with a reflective material 410, or formed from areflective material. In this implementation, the frusto-conical vesseland the column 402 can define a unitary structure (e.g., a drawn ormolded polymer structure) with the base 406, and the column can thusfunction like the reflective insert to constrain a local volume of fluidin the canister to a shallow depth relative to the imaging system.However, the canister and the reflective insert (or correspondingsurface integrated into the structure of the canister) can define anyother geometry or include any other suitable material. The column maycomprise a cylindrical shape, or may comprise a polygonalcross-sectional shape with at least one planar surface, such as arectangle or square. In other embodiments, e.g., as depicted in FIGS. 4Band 4C, the canister 412, 414 may comprise a projection or outwardlyfacing interior wall 416, 418 within internal volume 420, 422 that isintegrally formed with or attached to the sidewall 424 or lid 426 of thecanister, 412, 414, respectively. For example, the canister 412 in FIG.4B comprises a flanged arcuate wall 416 that is offset from the base 428of the canister 412 and the sidewall 424 but attached at one or bothedges 426 to the sidewall 424. The offset may permit the fluid level inthe canister to rise between the sidewall 424 and the arcuate wall 416,while still permitting agitation of the base 428 of the canister 412. InFIG. 4C, the wall 428 is attached to the underside of the lid 426, andpermits unimpeded fluid flow around the wall 428 as the internal volume422 is filled, and also permits unimpeded agitation of the base 430 ofthe canister 414.

Referring back to FIG. 1, the system 100 can also include a lid 144configured to cover and/or seal an upper opening 146 in the canister102. In one implementation, the lid 144 includes an inlet port 148configured to couple to a suction wand 140; and an outlet port 150configured to couple to a vacuum pump 134 (via an optional primarycanister 138) using vacuum lines 152, 154. In the implementation shownif FIG. 5A, the lid 144 is also depicted with an optional sump pickup156 extending from the lid 144 to the base 158 of the canister 102 andin fluid communication with the vacuum port 160; and a two-way valve 162configured to selectively connect the outlet port 150 to an upper volume152 of the canister 102 in a first position and to the vacuum port 160of the sump pickup 156 in a second position. In particular, with thevalve 162 in the first position, the lid 144 can communicate vacuum froman external vacuum source 134 into the canister 102 just below lid 144.Thus, the canister can communicate vacuum to the suction wand 140 todraw fluid into the canister 102. However, when the valve 162 is in thesecond position, the lid 144 communicates vacuum from the externalsource 134 to the sump pickup 156 such that fluid is drawn up the sumppickup 156, through the vacuum port 160 in fluid communication with thesump pickup 156, and into a remote fluid collector (e.g., to a primarycanister 138). In this implementation, the valve 162 can be manuallyactuated by a user on a switch 164 or button (or other mechanicalmechanism on the valve 162) when the canister is sufficiently full offluid in order to drain the contents of the canister into anothercontainer (e.g., a primary canister), or the system can automaticallyswitch the valve between the first and second positions via a solenoidor other valve control mechanism, such as when the weighing scale 106indicates that a threshold mass of fluid (corresponding to anapproximate threshold volume of fluid in the canister based on an 160estimated fluid density of ˜1030 kg/m³) is contained in the canister 102or when an output state of a float sensor in the lid changes, therebyindicating that a preset fill level limit has been reached.Alternatively, the user may also control the valve electronically viathe processor or other user interface. Also, although the valve 162 inFIG. 5A is depicted as separate from the lid 144, in other variations,the valve, the vacuum port to the sump pickup, and the fluid linetherebetween may be integrally formed or housed within the lid, suchthat only an inlet to be attached to a suction wand or catheter, and anoutlet port from the integrated valve, are provided on the lid. Wherethe valve is electronically controlled, a wired data interface may beprovided on the lid, or a wireless communication module to the computerdevice may be provided.

In the particular example in FIG. 5B, the fluid level sensor maycomprise a float sensor mechanism 166 configured to travel up and downalong the sump pickup 156. The float sensor mechanism 166 may beconfigured to close electrodes on the underside of the lid 144 uponreaching a designated fluid level, to provide a signal via a floatsignal interface 168 in communication with the processor to detectcanister volume. In other variations, the float sensor mechanism may bea visual aid for the imaging system to detect the fluid level. In stillother examples, the fluid level sensor may be comprise a series of fluidcontact electrodes 170 as shown in FIG. 5C along the length of the sumppickup 156. Different pairings of the electrodes 168 may be checked viathe float signal interface 168 in communication with the processor todetermine the fluid level based upon the closed electrode loop formed bythe fluid. The fluid level sensor may also be provided on a verticalstructure separate from the sump pickup, including but not limited tothe inner wall of the canister.

The scale 106 may also be used to detect other activity relating to thecanister 102 For example, removal of the canister 102 may be detected sothat the processor 132 can store the last or final concentration andvolume information from the removed canister 102 and reset anycounter(s) or register(s) for measuring any new canister. Weightoscillations resulting from intermittent suctioning of fluid when thesuction wand 140 is adjacent to fluid-air interface may occur, and theprocessor may be configured omit or correct for transient peaks in thedetected weight.

The canister can also include a disposable agitator element configuredto be remotely actuated by an agitator driver in the mount. For example,the canister 600 depicted in FIG. 6A can include a magnetic stirringelement 602 configured to run between the wall 604 of the canister 600and the reflective insert 606 (or between the column extending from thebase of the canister, as described above). In this example, when theagitator driver 608 in the mount 610 is actuated, the agitator driver608 (e.g., a motor) can be magnetically coupled to the magnetic stirringelement 602 through the wall 604 and can translate or draw the magneticstirring element in an arc about the axis of the canister 600, betweenthe wall of the canister and the reflective insert—to disrupt andredistribute sediment that may have collected in the bottom of thecanister. FIG. 6B depicts a top view of the reflective insert 606 with alow-profile base 612 configured to sit on the base of the canister and aprotruding reflective segment 614. In this variation the reflectivesurface does not form a complete 360 degree arc, so that the stirringelement 602 may transmit some agitation force to the shallow regionbetween the canister wall and the reflective segment 614. The agitatordrive 608 may also be configured to spin the stirring element 602 as ittranslates the stirring element 602 back and forth along an arc pathalong the wall 604 of the canister 600. In this particular example, theagitator driver 608 is positioned about a sidewall of the mount 610, butin other examples, the agitator driver may be positioned about the lowerwall of the mount. The agitator drive 608 may also be configured to spinthe stirring element 602 as it translates the stirring element 602 backand forth along an arc path along the wall 604 of the canister 600. Inthis particular example, the agitator driver 608 is positioned about asidewall of the mount 610, but in other examples, the agitator motor maybe positioned about the lower wall of the mount or even on its base.

In another example depicted in FIG. 6C, the canister 620 may include acentrally spinning magnetic stirring element 622 configured to reside ina central recess 624 of a ring-shaped reflective insert 626. As shown inFIG. 6D, the insert 626 may comprise segmented reflective structures 628with radial flow spaces 530 therebetween to facilitate indirect mixingof the canister contents located in imaging region 632 of the canister610 between the inner wall 634 and the segmented reflective structures628. The agitator motor or driver 636 may be located in the bottom wall638 of the mount 640, surrounded by the scale 642. In otherconfigurations, however, the scale may be mounted below the agitatordriver, and essentially monitors of the weight of the entire mount,computing device, canister and canister contents, such that prior toinitiating blood monitoring, the tare weight of mount, computing deviceand empty canister is measured to provide a corrective value and zerothe measured weight prior to fluid collection.

In another variation, depicted in FIGS. 6C and 6D, the mount 640includes an agitator driver 636 configured to couple to an agitatorelement 622 arranged within the canister 620 For example, the agitatordriver 636 can include a magnetic element 644 (e.g., an electromagnet, arare-earth magnetic) eccentrically mounted to a rotary motor 646arranged below the base 638 of the mount 640. In this example, thesystem can intermittently actuate the rotary motor 646, thereby rotatingthe magnetic element 644, which magnetically couples to and rotates theagitator element 622, thereby dispersing sediment collected on the baseof the canister and/or agitating contents in the canister to achieve amore uniform mixture of fluid, solids, particulate, etc. (e.g., redblood cells, plasma, saline, fat, clotted blood, etc.) in the canisterprior to imaging.

The centrally spinning magnetic stirring element 622 may be configuredto reside in a central recess 624 of a ring-shaped reflective insert626. As shown in FIG. 6D, the insert 626 may comprise segmentedreflective structures 628 with radial flow spaces 530 therebetween tofacilitate indirect mixing of the canister contents located in imagingregion 632 of the canister 610 between the inner wall 634 and thesegmented reflective structures 628. The agitator driver 636 may belocated in the bottom wall 638 of the mount 640, surrounded by the scale642. In other configurations, however, the scale may be mounted belowthe agitator driver, and essentially monitors of the weight of theentire mount, computing device, canister and canister contents, suchthat prior to initiating blood monitoring, the tare weight of mount,computing device and empty canister is measured to provide a correctivevalue and zero the measured weight prior to fluid collection.

In still another example depicted in FIG. 6E, the canister 650 comprisesa rotatable paddle 652 with a central drive shaft 654 and verticalpaddle elements 656 attached to the central drive shaft 644 viahorizontal paddle elements 658. The vertical paddle elements 656 areconfigured to directly agitate the imaging space 660 between the wall662 and the reflective structure 664. In this particular example, thedrive shaft 644 protrudes from the base 666 of the canister 650 and aseal 688 is provided to resist canister leakage. The drive shaft 644 isreceived in a drive shaft recess 670 rotated by a motor 672.

However, the canister can include any other suitable type of agitatorelement remotely configured to be remotely actated to stir orredistribute contents of the canister. Additional examples are providedbelow.

1.3 Imaging System

Referring back to FIG. 1, the imaging system may generally include: anoptical emitter 128 configured to illuminate the reflective insert 116through the translucent section 114 of the canister 102; and a camera130 configured to capture a digital photographic image of a volume offluid contained in the canister 102. Generally, the camera 130 functionsto capture digital color (e.g., photographic) images of a volume offluid in the canister 102. For example, the camera 130 can include adigital (e.g., CMOS or CCD) RGB camera. The optical emitter 128 istypically offset (e.g., laterally) from the camera 130 and configured toilluminate a volume of fluid contained in the canister 102 for imagingby the camera 130. In particular, the optical emitter 128 may beconfigured to output a controlled amount of light (e.g., light flux,lumens) such that the camera 130 can repeatedly capture color datathrough a depth of the fluid in the canister 102 despite ambientlighting conditions. In particular, the optical emitter 128 may outputsufficient light and camera 130 may capture images with sufficientlyfast shutter speeds such that images captured by the camera containcolor data of sufficiently quality to be transformed into sufficientlyaccurate estimations of the concentration of one or more bloodcomponents in the canister 102, and such that the effect of ambientlight on the color of the volume of fluid recorded in an image isrelatively insignificant.

In one implementation, the imaging system 126 may include a camera 130and a flash element or optical emitter 128 integrated into a standalonecomputing device, such as a smartphone, a tablet, or a personal mediaplayer. In this implementation, the computing device can execute anative image processing application that locally performs the methoddescribed below. The computing device can also include a display 180,opposite the camera 130 and an optical emitter 128, and configured todisplay or render a weight or volume of contents of the canister 102, acomposition of fluid contained in the canister 102 (e.g., aconcentration or volume fraction of hemoglobin, red bloods cells, orwhole blood, etc. in the canister); and/or notifications, such as aprompt to empty the canister if fluid in the canister is approaching amaximum fill level, a prompt to empty the canister or to stir thecontents of the canister if sediment is obscuring the camera, or aprompt to salvage red blood cells from the contents of the canister,such as described below.

1.4 Mount

As shown in FIGS. 1, 2A and 2B, the mount 104 is typically configured toengage an exterior surface 118 of the canister 102. The mount 104 mayalso comprise or define a first window 120 configured with a firstsurrounding seal 122 a/b to seal over the exterior surface 118 of thecanister 102 proximal the translucent section 114, and to furthercomprise or define a second window 124 adjacent the first window 120 andconfigured with a second surrounding seal 182 a/b to seal over theexterior surface 118 of the canister proximal the translucent section,wherein the first window is substantially optically isolated from thesecond window. Generally, the mount is configured to support the opticalemitter 128 and the camera 130 adjacent and facing the canister 102 andto isolate the camera 130 from light outside of the canister, e.g.,ambient light, light output by the optical emitter 128 but not reflectedby or refracted through fluid in the canister 102.

The mount 104 is configured to receive and support the base 158 of thecanister 102. In one example, the mount 104 defines a frusto-conicalreceptacle 184 sized to fit the canister 102, as shown in FIG. 2A, andincludes an optional latch 186 configured to transiently mate with arecess or an engagement feature 188 on the vessel 102, therebyconstraining the canister 102 in the mount. In this example, thecanister 102 can be inserted into the receptacle 184, and the latch 186can engage the canister 102 once the base 158 of the canister 102 meetsthe base 190 of the receptacle 184; the latch 186 can then be withdrawnto release the canister 102 for disposal or emptying. In a similarexample, the mount can include a conical receptacle defining a conicalangle matched to the conical angle of the canister. In this example, thecanister can be inserted into the conical receptacle, and the weight ofthe canister can compress the walls of the canister against the interiorsurface of the conical receptacle. In another example, the mountincludes a belted or elastic strap configured to wrap around a canisterand to retain an interior surface of the mount against an exteriorsurface of the canister. The canister may also be configured with agroove or recess to receive the strap. In the foregoing examples, themount can define first and second windows—for the optical emitter andthe camera, respectively—that intersect the interior surface of thereceptacle to meet the exterior surface of a canister when the canisteris installed in the mount.

In one implementation, the mount 104 comprises a computing devicereceptacle 192 that is configured to transiently receive a standalonecomputing device 131 (as described above) and to support the computingdevice 131 with its camera 130 and optical emitter 128 or flash elementfacing the canister 102, as shown in FIG. 1. For example, the mount 104can support the computing device 131 in a vertical orientation such thatthe optical axis of the camera 130 is substantially normal to anadjacent exterior surface 118 of the canister 102; proximal the base 158of the canister 102 to optically detect and analyze a relatively smallvolume of fluid in the canister through the transparent region 114 ofthe canister 102 located between the canister wall 142 and thereflective insert 116, and vertically offset above the base 158 of thecanister 102 such that a volume of sediment may collect on the base 158of the canister 102 without immediately obscuring the optical emitterand/or the camera, as shown in FIG. 2A. The mount 104 can also supportthe computing device 131 at an offset from the wall 142 of the canister102 such that a minimum width and/or height of the reflective insert 116remains within the field of view of the camera 130.

However, the mount can define any other geometry or function in anyother way to transiently couple the optical emitter and the camera tothe canister, and vice versa. In some variations, the computing devicereceptacle may be a modular or adjustable receptacle, to permit the useof different computing devices with the system, e.g. an IOS, Android,Windows or Linux tablet/cellphone, or camera system. In some othervariations, a lens may be provided in the optical path of the secondwindow corresponding to the camera 130. A lens may facilitate focusedimage capture, which may be used to detect and/or characterize sedimentor other materials found in the canister.

The mount 104 defines a first window 120 configured to align with theoptical emitter 128 and a second window 124 configured to align with thecamera 130. In particular, the first window 120 is configured to passlight from the optical emitter 128 to the wall 142 of the canister 102,which passes light into fluid in the canister 102 and onto thereflective insert 116, thereby illuminating the fluid and the reflectiveinsert 116; the second window 124 is configured to pass light reflectedand refracted out of the wall 142 of the canister 102 by the reflectiveinsert 116 and the fluid into the camera 130. The mount 104 can includea first seal 122 a around a perimeter of a first side of the firstwindow 120 and configured to seal the first window 120 against theexterior surface 118 of the canister 102 when the canister 102 isinstalled in the mount 104; a second seal 122 b around a perimeter ofthe opposite side of the first window 120 and configured to seal thefirst window 120 against an exterior surface of the computing device131—around the optical emitter 128—when the computing device 131 isinstalled in the mount 104, as shown in FIG. 2B. In some examples, thefirst seal 122 a and the second seal 122 b may an integrally formedwindow seal or grommet spanning both surfaces of the window 120.Similarly, the mount can include: a third seal 182 a around a perimeterof a first side of the second window 124 and configured to seal thesecond window 124 against the exterior surface 118 of the canister 102when the canister 102 is installed in the mount 104; a fourth seal 182 baround a perimeter of the opposite side of the second window 124 andconfigured to seal the second window 124 against an exterior surface 118of the computing device 131—around the camera 130—when the computingdevice 131 is installed in the computing device receptacle 184 of themount 104. The third and fourth seals 182 a/b may be separate seals oran integrally formed window seal or grommet spanning both surfaces ofthe second windows 124. In some further examples, a single figure-eightseal may be used for the optical emitter 128 and camera 130. The seals122 a/b and 182 a/b can include opaque flexible seals to minimizecrosstalk (e.g., light bleed) between the optical emitter 128 and thecamera 130 outside of the canister 102. For example, the mount 104 caninclude soft, black silicone O-rings configured to abut and compressbetween the inter-recess wall structure 194 of the mount 104 and thecanister 102 (e.g., the first and third seals 122 a, 182 a) and to abutand compress between the inter-recess wall structure 194 of the mount104 and the computing device 131 (e.g., the second and fourth seals 122b, 182 b).

1.5 Weighing Scale

Referring back to FIG. 1, the weighing scale 106 may be coupled to themount 104 and be configured to output a signal corresponding to a weightof contents in the canister 102. In one implementation, the mount 104 ofthe system 100 is configured to rest on a horizontal surface, and theweighing scale 106 is coupled to the mount 104 opposite the canister 102and outputs a signal corresponding to the weight of the mount 104, thecomputing device 131, the canister 102, fluid in the canister, etc.above, as shown in FIG. 2A. In this implementation, the weighing scale104 can include a footing or resilient friction pad 196 configured tosit on a horizontal surface and a strain gauge 198 interposed betweenthe mount 104 and the footing 196. In another implementation, the systemis configured to hang, such as from a hook on the operating room tableor IV pole, and the weighing scale is arranged between the lid and thehook and configured to output a signal corresponding to the weight ofthe mount, the computing device, the canister, the lid, fluid in thecanister, etc. below. However, the system can include a weighing scaleof any other type and coupled to the mount or to the canister in anyother suitable way.

In some embodiments, the processor may receive weight information fromthe scale in a continuous or a variable manner. The sampling rate forthe weight may be in the range of about 1000 Hz to about once every 5minutes, or about 60 Hz to about 1 Hz. In some variations, when thedetected rate of fluid weight increase is higher or in a certain range,the sampling rate of the scale may be increased, as well as imagecapture rate or illumination rate of the imaging system.

The scale may also be used to indicate other states of events relatingto canister use. For example, the complete unweighting of the scale, orreduction of weight below the tare weight of the canister, may be usedto indicate removal of the canister. During use of the vacuum system,the detected weight may increase in a generally linear fashion whilesuctioning liquid material, but may exhibit some variation whensuctioning mixtures of liquid and solid or semi-solid materials ortissue. The weight may also oscillate when the suction device is used ata liquid/air interface and the processor of the system may be configuredto detect such states and to wait for the oscillations to stop beforereporting any weight changes.

1.6 Processor

As noted previously, the system typically comprises a processor that maybe configured to transform an image captured by the color camera into anestimated concentration of a blood component in a fluid within thecanister and to estimate an amount of the blood component in thecanister based on the estimated concentration of the blood component andan output of the weighing scale. Generally, the processing functions tolocally execute one or more aspects of the method described below.

In the implementation described above in which the optical emitter 128and the camera 130 are integrated into a standalone computing device131, as shown in FIG. 1, the processor 132 can be similarly integratedinto the computing device 131. In this implementation, the computingdevice 131 can communicate with the weighing scale 106 and/or with anelectromechanical valve coupled to the lid or in the lid via a wiredconnection to a port in the computing device. Alternatively, the systemcan include a short-range wireless communication module, such as NFC orBluetooth or wireless USB, electrically coupled to the weighing scaleand/or to the electromechanical valve, and the computing device 131 canwirelessly pair with the wireless communication module to receiveoutputs from the weighing scale and/or to control the state of thevalve.

In another variation, the camera, the optical emitter, the digitaldisplay, and the processor are integrated into the mount. However, thesystem can include any other integrated or discrete elements thatcooperate to collect fluid from a suction wand, to weigh the fluid, toimage the fluid, to transform images of the fluid into estimations ofthe quality of the fluid, and to generate estimations of the quantity ofone or more blood components in the fluid over time.

2. Method

FIG. 3 depicts an illustrative method that may be suitable for use withthe systems described herein. As shown there, a method S100 forestimating an amount of a blood component in a volume of fluid mayinclude illuminating an insert 116 within a canister 102 according to anillumination schedule; capturing an image of the insert (via an opticaldetector or camera offset from the optical emitter), estimating aconcentration of a blood component in a fluid within the canister e.g.,based on the illumination schedule, color intensities of pixels in theimage, and a color gradient from a first region to a second region inthe image, where the first region corresponds to proximity to theoptical emitter, and the second region corresponds to remoteness fromthe optical emitter.

2.1 Applications

Generally, one or more portions the method may be executed locally bythe system 100 described above to automatically capture an image of a(sub)volume of fluid contained in a canister 102 and to transformabsolute color values in the image and/or color gradients across pixelsin the image into a quantitative estimation of a concentration of ablood component in the canister 102. For example, the system 100 maytransform an image into an estimation of a mass per unit volume ofhemoglobin, a volume fraction of red blood cells, or a volume fractionof whole blood, etc. of fluid contained in the canister. In particular,the system 100 may actuate an optical emitter to illuminate the volumeof fluid in S110, triggers a camera to capture an image in S120, andprocesses the image to generate a blood component concentrationestimation in S130. As noted previously, the light source or opticalemitter and the camera or optical detector may be provided in thecomputing device 131, or may be integrated into the mount 104.

The method described herein may be executed locally by the system, e.g.the computing device 131, for estimating an amount of a blood componentin a volume of fluid described above. However, portions of the methodmay additionally or alternatively be executed remotely from the system,such as by another local computing device connected to the system, by alocal distributed network, or by a remote server.

2.2 Image Capture

The method may further comprise at S110 illuminating an insert 116within a canister 104 according to an illumination schedule (e.g., usingan optical emitter); and at S120, capturing an image of the insert 116(e.g., using an optical detector). Generally, the system is configuredto illuminate the reflective insert 116 within the canister 102—andtherefore a volume of fluid between the reflective insert and thecamera—and to capture an image of the illuminated volume of fluidlocated between the insert 116 and the wall 142 of the canister 102.

In one implementation, to capture an image of a volume of fluid in thecanister, the system 100 powers on the optical emitter at a static,preset illumination power in S110, triggers the camera to capture animage in S120, and then deactivates the optical emitter. The power levelmay be in the range of 1 lumen to 1,000 lumens, or about 3 lumens toabout 100 lumens, or about 3 lumens to about 50 lumens, or about 5lumens to about 20 lumens, or about 15 lumens to 30 lumens, about or maybe anywhere from 1% to 100% or about 30% to about 100%, or about 70% toabout 100% of the light source's maximum power.

In another implementation, to capture an image of a volume of fluid inthe canister 102, the system 100 first activates the optical emitter ata select illumination power, such as by pulse-width modulating theoptical emitter at a selected duty cycle, in order to achieve targetbrightness in an image subsequently captured by the camera. For example,the system 100 can pulse-width modulate the optical emitter at frequencygreater than a fastest shutter speed implemented by the camera (e.g.,500 Hz for a camera operable at a maximum shutter speed of 1/100 s). Thesystem then triggers the camera to capture an image in Block S120, suchas 0.002 second after the optical emitter is activated in Block S110.Once the image is recorded in Block S120, the system can deactivate theoptical emitter.

In some other embodiments, the processor may be configured to initiateimage capture upon a signal from the scale indicating a change in theweight of the canister contents.

In the foregoing implementation, the system 100 can progress through aset of duty cycles—such as down from 100% duty or up from 0% in 1%, 5%,10%, 20% duty increments—and capture an image at each duty until thecamera captures an image that meets one or more target color parameters,such as a lightest color limit, a darkest color limit, or target colorgradient between the first region and the second region of the image. Inone exemplary implementation, the system can increase the duty cycle ofthe optical emitter—starting at 0%—and capture an image for each dutycycle through the camera until a captured image contains a contiguoushorizontal line of pixels containing less than a threshold number ofblack pixels or pixels darker than a threshold dark color value. Forexample, once an image is captured by the camera, the system can scan asingle horizontal line of pixels centered vertically in the image andcount a number of consecutive pixels (or a total number of pixels) alongthe scan line containing the color black or containing a color valueless than (i.e., darker than) a threshold darkness value. In thisexample, if the number of consecutive pixels (or total number of pixels)along the scan line exceeds a threshold count, the system can reject theimage, increase the duty cycle of the optical emitter, capture asubsequent image through the camera, and similarly process thesubsequent image. The system can repeat this process until a final imagewith a number of consecutive pixels (or total number of pixels) along ascan line less than the threshold count is captured. The system can thenprocess this final image in Block S130, as described below.

In another exemplary implementation, the system can decrease the dutycycle of the optical emitter—starting from 100%—and capture an image foreach duty cycle through the camera until a captured image contains acontiguous horizontal line of pixels containing less than a thresholdnumber of white pixels or pixels lighter than a threshold light colorvalue.

In the foregoing exemplary implementations, for a subsequent samplingperiod, the system can repeat the foregoing process, starting with a lowduty cycle (e.g., 0%) or a high duty cycle (e.g., 100%) at the opticalemitter and then increase or decrease the duty cycle, respectively,until a suitable image is captured at the camera. Alternatively, thesystem can begin a new imaging period by setting the optical emitter toimplement a last duty cycle from the preceding imaging period. Thesystem can then capture a first image in the new imaging period throughthe camera, either increase or decrease the duty cycle of the opticalemitter if the first image contains an excess number of black or darkpixels or if the first image contains an excess number of white or lightpixels, respectively, capture and process a subsequent image, and thenrepeat the foregoing until an image containing color data of suitablequality is achieved. In these implementations, the system can thus varythe illumination power output by the optical emitter and process imagescaptured under various illumination powers in order to identify andrecord an image containing a suitable quality of color data that can betransformed into a quality (e.g., a blood component concentration) of avolume of fluid in the canister.

Additionally or alternatively, the system may set an illumination power(by setting a duty cycle) of the optical emitter and then vary theshutter speed of the camera—and therefore an exposure of an imagecaptured with the camera—to achieve an image with a quality of colordata suitable for transformation into a quality of the volume of fluidin the canister. For example, the system may operate the optical emitterat a duty cycle of 100%; decrease the shutter speed of the camera (e.g.,from 1/200 s to 1/100 s, then 1/30 s, 1/20 s, 1/15 s, 1/12 s, etc.); andcapture an image through the camera for each shutter speed until acaptured image contains a contiguous horizontal line of pixelscontaining less than a threshold number of black pixels or pixels darkerthan a threshold dark color value.

In the foregoing implementations, the system may implement any othermethod or technique to set an illumination power, a shutter speed, orany other illumination or image-capture parameter for the imagingsystem. Similarly, the system may implement any other method ortechnique to confirm that an image captured by the camera—for a givenset of illumination and image-capture parameters—contains sufficientcolor data for transformation into a quality of fluid within thecanister. The system may also manipulate multiple illumination and imagecapture parameters—such as both a duty of the optical emitter and ashutter speed of the camera—to achieve a target color quality in animage.

The system can therefore capture multiple images during a single imagingperiod and discard all but a single image containing sufficient colordata for transformation into a quality (e.g., a blood componentconcentration) of a volume of fluid contained in the canister. Thesystem may tag this select image with illumination and/or image captureparameters executed by the imaging system to capture the select image,such as the duty implemented by the optical emitter and/or the shutterspeed implemented by the camera when the select image was captured. Inorder to transform the select image into a fluid quality in Block S130,the system can then select a set of template images based on theseillumination and image capture parameters for comparison to the selectimage or insert these illumination and image capture parameters into aparametric model that is then applied to color values in select images,as described below.

In one variation, the system captures multiple images at differentillumination and/or image-capture parameters in Blocks S110 and S120.For example, in a single imaging period, the system may: set the opticalemitter at 0% duty and capture a first image; set the optical emitter at50% duty and capture a second image; and then set the optical emitter at100% duty and capture a third image. In another example, the system may:step the duty of the optical emitter upward from a minimum duty (e.g.,0%); capture an image at each duty step; store a first image including atotal number of black pixels less than a threshold number of blackpixels; and store a last image including a total number of white pixelsless than a threshold number of white pixels (or vice versa). In yetanother example, the system may: set the duty cycle of the opticalemitter (e.g., at a static value of 80%); step the shutter speeddownward from a maximum shutter speed (e.g., 1/200 s); capture an imageat each shutter speed; store a first image including a total number ofblack pixels less than a threshold number of black pixels; and store alast image including a total number of white pixels less than athreshold number of white pixels (or vice versa).

However, the system may manipulate any other illumination and/or imagecapture parameter across a set of images. The system may then processthis set of images in Block S130 to estimate a quality of the fluidwithin the canister during the corresponding imaging period.

2.3 Blood Component Concentration

Block S130 of the method depicts, color intensities of pixels in theimage 300, and a color gradient 302 from a first region 304 to a secondregion 306 in the image 300, estimating a concentration of a bloodcomponent in a fluid within the canister, the first region 304corresponding to proximity to the optical emitter, and the second region306 corresponding to remoteness from the optical emitter. Generally, inBlock S130, the system transforms color values contained in pixels in animage 300 captured by the camera into one or more of: a concentration ofred bloods cells; a concentration of hemoglobin; a proportion of wholeblood cells to lysed red blood cells (or free hemoglobin); aconcentration of whole blood; a concentration of plasma; a concentrationof white blood cells; etc. in a volume of fluid contained in thecanister. In particular, the system can implement parametric and/ornon-parametric (e.g., template-matching) techniques to transform colordata contained in an image 300 captured by the camera into a bloodcomponent concentration value for a volume of fluid contained in thecanister, such as described, for example, in U.S. patent applicationSer. No. 13/544,664 and Ser. No. 13/738,919.

In one implementation, the system implements template matchingtechniques to match one or more color values (e.g., intensity in the redcolor space) in an image captured by the camera to a template image of afluid of known blood component concentration and stored in (local orremote) memory. In one example implementation, the system can match acolor gradient from a first side of the image (corresponding to ashortest distance to the optical emitter) to an opposite side of theimage (corresponding to a greatest distance from the optical emitter) toa template gradient of one or more known blood component proportions. Inthis exemplary implementation, the system may select a single templateimage containing a lightest color, a darkest color, and/or a linear ornon-linear color gradient nearest the lightest color, darkest color,and/or color gradient represented in the current image and assign one ormore blood component concentration values associated with the templateimage to the current image. Similarly, the system may select two or moretemplate images exhibiting lightest colors, darkest colors, and/or colorgradients nearest those of the current image and then average bloodcomponent concentration values associated with these template images togenerate an estimation of a blood component concentration in thecanister at a time the current image was captured.

In the foregoing implementation, the system may apply template imagesfrom multiple template image sets—each image template set correspondingto a subset of known blood component concentration values—to the currentimage in order to generate estimations of multiple blood componentconcentrations representative of a volume of fluid contained in thecanister from a single image of the canister. For example, the systemmay match a difference between a lightest color value and a darkestcolor value in the current image to a template image in a first templateimage set to generate an estimation of the concentration of hemoglobinin the volume of fluid in the canister; the system may then match anon-linear color gradient between the first side of the image and thesecond side of the image to a template image in a second template imageset to generate an estimation of the proportion of lysed red blood cellsin the volume of fluid in the canister.

Furthermore, in this implementation, the system may select or filteravailable template images based on illumination and image-captureparameters implemented by the imaging system to capture the currentimage. For example, the system may set the duty of the optical emitterat 70% percent, capture an image, and then select a template image setcontaining template images captured by similar systems with opticalemitters operating at 70% duty. In another example, the system may setthe duty of the optical emitter at 100% percent, set the shutter speedof the camera at 1/20 s, capture an image, and then select a templateimage set containing template images captured by similar systems withoptical emitters operating at 100% duty and cameras operating at ashutter speed of 1/20 s.

However, in this implementation, the system may implement any othermethod or technique to select a template image of known blood componentconcentration and to match the template image to a current imagecaptured by the camera to generate an estimation of a blood componentconcentration in a volume of fluid contained in the canister at a timethe current image was captured.

In another implementation, the system passes quantitative datarepresented in one or more pixels in the current image into a parametricmodel that outputs a quantitative estimation of the concentration of oneor more blood components in a volume of fluid contained in the canister,as shown in FIG. 3. For example, the system may pass a color value in asingle lightest pixel (or in a small cluster of lightly-colored pixels)and a color value in a single darkest pixel (or in a small cluster ofrelatively dark pixels) in the current image into the parametric model.In another example in which the camera captures an image 2000 pixelswide and 1000 pixels tall, the system can: separate the current imageinto ten 200-pixel-wide, 1000-pixel tall columns; average the intensityof each column in the red, green, and blue component spaces; and passthese thirty intensity values into a parametric model that transformsthese values into an estimation of the concentration of one or moreblood components in the volume of fluid in the canister at the time thecurrent image was captured.

The system may also calculate coefficients of a linear, logarithmic,polynomial, power, or other trendline of the color gradient from thefirst region of the image (e.g., a pixel or pixel cluster of lightestcolor) to the second region of the image (e.g., a pixel or pixel clusterof darkest color) and pass these coefficient values into a parametricmodel. The system may also identify a trendline type (e.g., linear,logarithmic, or polynomial, etc.) that best fits the color gradientrepresented in the current image, select a parametric model for theidentified trendline type, and then pass coefficients of a trendline ofthe identified trendline type into the selected parametric model togenerate an estimation of the concentration of the blood component inthe canister.

In this implementation, in addition to color values of pixels in thecurrent image, the system may also pass illumination and/orimage-capture parameters implemented by the imaging system to capturethe current image—such as a duty of the optical emitter or the shutterspeed of the camera—into the parametric model. Alternatively, the systemmay select a particular parametric model from a set of availableparametric models based on the illumination and/or image-captureparameters implemented by the imaging system to capture the currentimage; the system may then pass color values of pixels in the currentimage into the selected parametric model to output an estimation of ablood component concentration in the canister.

In the variation above in which the system captures multiple imagesthrough the camera in a single imaging period, the system may alsoimplement any of the foregoing methods and techniques to compareabsolute color values or color gradients across two or more images in aset of images. For example, the system may capture two images of thevolume of fluid in the canister under two distinct lighting conditions(e.g., 20% duty and 80% duty at the optical emitter) and thencharacterize a difference in the color gradients across both images as aconcentration of whole red blood cells and a concentration of freehemoglobin in the volume of fluid in the canister.

However, the system may implement any other parametric or non-parametrictechniques to transform color data contained in one or more imagescaptured by the camera into an estimation of a quality of a volume offluid contained in the canister.

2.4 Image Quality

In one variation, the system determines a quality of an image output, asdepicted in Block S120, and selectively discards this image or passesthis image on to the next step of the process. In one implementation,the system scans the image vertically (e.g., along one or more verticalcolumns of pixels in the image) for a sharp shift in color value from alower region of the image to an upper region of the image. The systemmay then correlate this color shift with collection of sediment on thebottom of the vessel, discard the image, and/or trigger manual orautomatic removal of sediment from the field of view of the camera ifsuch a color shift is detected in the image. In particular, due toproximity of the optical emitter to the camera, as sediment collects onthe bottom of the canister and obscures the field of view of the camera,sediment may similarly obscure projection of light from the opticalemitter onto the reflective insert such that sediment in the field ofview of the camera remains substantially dim compared to the reflectiveinsert when the optical emitter is actuated. Therefore, an imagecaptured by the camera after sediment has collected in the field of viewof the camera may contain a contiguous column of relatively dark pixelscorresponding to a segment, extending upwardly from the bottom of theimage, and rapidly transitioning into a contiguous column of relativelybright pixels corresponding to the reflective insert (and to fluidbetween the wall of the canister and the reflective insert). The systemmay scan one or more vertical columns of pixels in an image captured bythe camera and then discard the image as containing insufficient colordata of the fluid if a column of pixels in the image includes atransition from a line of dark pixels to a line of light pixels (or ifthe image includes more than a threshold number of dark pixels in avertical column of dark pixels below a line of light pixels).

In one example, if a color shift is detected in an image, the system canissue an audible or visual prompt (e.g., through the display) to agitatethe contents of the vessel. The system can then sample an integratedaccelerometer to determine if the canister has been agitated or continueto capture and analyze images to determine if sediment has been removedfrom the field of view of the camera. Alternatively, if a color shiftindicative of obscuration of the camera is detected in an image recentlycaptured by the camera, the system can automatically activate anagitator—as described above—to mix contents and redistribute sedimentwithin the canister prior to capturing. For example, the system canactivate the agitator for a preset period of time (e.g., 10 seconds) oruntil images captured by the camera no longer exhibit such a sharp shiftin color value. In this example, once a sharp color value shift is nolonger detected in the field of view of the color system, the system candeactivate the agitator, pause for a period of time (e.g., five seconds)to allow fluid within the canister to slow, and then execute BlocksS110, S120, and S130 as described above to capture and process an imageof fluid in canister.

Furthermore, in this variation, if sediment is detected in a currentimage but the current image contained sufficient color data to provide areliable estimation of the concentration of a blood component in thecanister, the system can remove (e.g., crop) a region of the currentimage correlated with obscuration by sediment and pass the remainder ofthe current image to Block S130 for processing. However, the system mayimplement any other method or technique to confirm the quality of imagescaptured by the camera and selectively pass on and/or reject theseimages.

2.5 Blood Component Quantity

While capturing images in Block S120, the system may also sample theweighing scale and apply a value output by the weighing scale to theblood component concentration value to estimate a quantity (e.g., avolume, a mass) of the blood component in the canister in Block S140. Inone implementation, the system 100 continuously samples the weighingscale and records outputs of the weighing scale 106 with correspondingtimestamps in memory. In this implementation, for an image captured inBlock S120 and processed in Block S130, the system 100 can retrieve—frommemory—a weighing scale output value (e.g., weight) recorded at a timenearest a time that the image 300 was captured. (The system 100 can alsoretrieve multiple weighing scale outputs recorded around the time thatthe image was captured and then average these values.) The system 100can then divide this weighing scale output value for the imaging periodby a static estimated density of fluid collected in the canister 102(e.g., 1030 kg/m³ for a mixture of saline and blood) to estimate thevolume of fluid in the canister. By then multiplying this estimatedvolume by the blood component concentration, the system can estimate thevolume (or mass) of the blood component (e.g., hemoglobin, red bloodcells) in the canister, as depicted in Block S150.

The system can repeat Blocks S110, S120, S130, S140, and S150 throughoutan operation—such as at a rate of 1 Hz—in order to update estimations ofa volume of fluid in the canister, a quality of the volume of fluid,and/or a quantity of a blood component in the canister over time.

2.6 Visual Feedback

Throughout operation, as shown in Block S100, the system 100 may updatean integrated display 180 over time to visually indicate a currentestimated volume of fluid in the canister 102, a current estimatedquality of the volume of fluid, and/or a current estimated quantity ofthe blood component in the canister 102, as shown in FIG. 3. The system100 may also render prompts on the display 180, such as a prompt toempty the canister 102 or a prompt to agitate the canister 102 due tocollection of sediment in front of the imaging system.

The systems and methods described herein can be embodied and/orimplemented at least in part as a machine configured to receive acomputer-readable medium storing computer-readable instructions. Theinstructions can be executed by computer-executable componentsintegrated with the application, applet, host, server, network, website,communication service, communication interface,hardware/firmware/software elements of a user computer or mobile device,wristband, smartphone, or any suitable combination thereof. Whenimplemented as a system, such system may comprise, inter alia,components such as software modules, general-purpose CPU, RAM, etc.found in general-purpose computers, and/or FPGAs and/or ASICs found inmore specialized computing devices. In implementations where theinnovations reside on a server, such a server may comprise componentssuch as CPU, RAM, etc. found in general-purpose computers. Other systemsand methods of the embodiment can be embodied and/or implemented atleast in part as a machine configured to receive a computer-readablemedium storing computer-readable instructions. The instructions can beexecuted by computer-executable components integrated bycomputer-executable components integrated with apparatuses and networksof the type described above. The computer-readable medium can be storedon any suitable computer readable media such as RAMs, ROMs, flashmemory, EEPROMs, optical devices (CD or DVD), hard drives, floppydrives, or any suitable device. The computer-executable component can bea processor but any suitable dedicated hardware device can(alternatively or additionally) execute the instructions.

In the present description, the terms component, module, device, etc.may refer to any type of logical or functional circuits, blocks and/orprocesses that may be implemented in a variety of ways. For example, thefunctions of various circuits and/or blocks can be combined with oneanother into any other number of devices. Or, the devices can compriseprogramming instructions transmitted to a general purpose computer or toprocessing/graphics hardware via a transmission carrier wave. Also, thedevices can be implemented as hardware logic circuitry implementing thefunctions encompassed by the innovations herein. Finally, the devicescan be implemented using special purpose instructions (SIMDinstructions), field programmable logic arrays or any mix thereof whichprovides the desired level performance and cost.

Aspects of the method and system described herein, such as the logic,may also be implemented as functionality programmed into any of avariety of circuitry, including programmable logic devices (“PLDs”),such as field programmable gate arrays (“FPGAs”), programmable arraylogic (“PAL”) devices, electrically programmable logic and memorydevices and standard cell-based devices, as well as application specificintegrated circuits. Some other possibilities for implementing aspectsinclude: memory devices, microcontrollers with memory (such as EEPROM),embedded microprocessors, firmware, software, etc. Furthermore, aspectsmay be embodied in microprocessors having software-based circuitemulation, discrete logic (sequential and combinatorial), customdevices, fuzzy (neural) logic, quantum devices, and hybrids of any ofthe above device types. The underlying device technologies may beprovided in a variety of component types, e.g., metal-oxidesemiconductor field-effect transistor (“MOSFET”) technologies likecomplementary metal-oxide semiconductor (“CMOS”), bipolar technologieslike emitter-coupled logic (“ECL”), polymer technologies (e.g.,silicon-conjugated polymer and metal-conjugated polymer-metalstructures), mixed analog and digital, and so on.

As a person skilled in the art will recognize from the previous detaileddescription and from the figures and claims, modifications and changescan be made to the embodiments of the invention without departing fromthe scope of this invention as defined in the following claims.

The invention claimed is:
 1. Apparatus comprising: a canister receptacleto receive a canister, the canister to receive fluid from a patient; aweight measurement element arranged to measure weight of the canisterincluding the fluid; an image capture device to capture of an image ofthe fluid, the capture device being triggered based on weightinformation from the weight measurement element; and a communicationinterface to communicate the weight information and image data to aprocessing unit that triggers the image capture device, the processingunit being configured to determine a hemoglobin value of the fluid inthe canister based on the weight and the image of the fluid.
 2. Theapparatus of claim 1, wherein the processing unit is configured totrigger the image capture device based on a change in the weight of thecanister.
 3. The apparatus of claim 1, wherein the processing unit isconfigured to receive the captured image in response to the imagecapture device being triggered based on a change in the weight of thecanister.
 4. The apparatus of claim 1, wherein the processing unit isconfigured to determine a hemoglobin value of the fluid in the canisterbased on the image of the fluid, and to modify the hemoglobin value ofthe fluid.
 5. The apparatus of claim 1, wherein the processing unit isconfigured to initiate a draining of the fluid from the canister, and toset a reference weight of the canister in response to completion of theinitiated draining of the fluid.
 6. The apparatus of claim 1, whereinthe processing unit is configured to detect removal of the canister fromthe canister receptacle based on the weight information, and to store atleast one of a fluid concentration value of the fluid in the canister ora fluid volume value of the fluid in the canister in response to thedetected removal of the canister.
 7. The apparatus of claim 1, whereinthe processing unit is configured to detect removal of the canister fromthe canister receptacle based on the weight information, and to reset atleast one of a counter corresponding to the fluid or a registercorresponding to the fluid in response to the detected removal of thecanister.
 8. The apparatus of claim 1, wherein the processing unit isintegral with the apparatus.
 9. The apparatus of claim 1, wherein theprocessing unit is remote from the image capture device and the weightmeasurement element.
 10. The apparatus of claim 1, wherein the image isof a sub-volume of the fluid in the canister.
 11. The apparatus of claim1, wherein the processing unit is configured to transform at least oneof absolute color values in the image or color gradients across pixelsin the image into a quantitative estimation of a concentration of ablood component in the fluid.
 12. The apparatus of claim 1, wherein theprocessing unit is configured to trigger an optical emitter to assistthe image capture device to capture the image.
 13. The apparatus ofclaim 12, wherein the optical emitter is configured to illuminate areflective insert in the canister, and the image capture device isconfigured to capture the image of the fluid between the reflectiveinsert and a wall of the canister.
 14. The apparatus of claim 1, whereinthe processing unit is configured to estimate a concentration of a bloodcomponent in the fluid based on the weight.
 15. The apparatus of claim1, wherein a display is caused to be updated to visually indicate atleast one of a current estimated volume of the fluid in the canister, acurrent estimated quality of the volume of the fluid, or a currentestimated quantity of a blood component in the canister.
 16. A systemcomprising: a canister; a scale; an imaging device; and a processorconfigured to cause the imaging device to capture an image of fluid inthe canister based on weight information from the scale, the processorbeing further configured to determine a hemoglobin value of the fluid inthe canister based on the weight and the image of the fluid.
 17. Thesystem of claim 16, further comprising: a communication moduleconfigured to provide the weight information from the scale to theprocessor.
 18. The system of claim 16, wherein the processor isconfigured to cause the imaging device to capture the image of the fluidin the canister in response to the weight information from the scaleindicating a change in a weight of the canister.
 19. The system of claim16, wherein the processor is configured to initiate a draining of thefluid from the canister, and to set a reference weight of the canisterin response to completion of the initiated draining of the fluid. 20.The system of claim 16, wherein the imaging device is arranged tocapture the image of the fluid through a first aperture in a wallbetween the canister and the imaging device.
 21. The system of claim 20,further comprising: an optical emitter configured to illuminate thefluid through a second aperture in the wall, the second aperture beingoptically isolated from the first aperture in the wall.
 22. A methodcomprising: monitoring, by one or more processors, a weight of acanister that contains fluid based on weight information from a scale;detecting, by the one or more processors, a change in the weight of thecanister that contains the fluid; causing, by the one or moreprocessors, an imaging device to capture an image of the fluid in thecanister in response to the change in the weight of the canister;providing, by the one or more processors, an estimated volume of thefluid in the canister based on the image caused to be captured inresponse to the change in the weight of the canister; and determining,by the one or more processors, a hemoglobin value of the fluid in thecanister based on the weight and the image of the fluid.
 23. The methodof claim 22, further comprising: estimating an amount of a fluidcomponent within the estimated volume of the fluid in the canister; andproviding the estimated amount of the fluid component.
 24. Apparatuscomprising: a canister receptacle to receive a canister, the canister toreceive fluid from a patient; a weight measurement element arranged tomeasure weight of the canister including the fluid; an image capturedevice to capture of an image of the fluid, the capture device beingtriggered based on weight information from the weight measurementelement; and a communication interface to communicate the weightinformation and image data to a processing unit that triggers the imagecapture device, the processing unit being configured to determine ahemoglobin value of the fluid in the canister based on the image of thefluid, and to modify the hemoglobin value of the fluid.
 25. A systemcomprising: a canister; a scale; an imaging device; and a processorconfigured to cause the imaging device to capture an image of fluid inthe canister based on weight information from the scale, the processorbeing further configured to determine a hemoglobin value of the fluid inthe canister based on the image of the fluid, and to modify thehemoglobin value of the fluid.
 26. A method comprising: monitoring, byone or more processors, a weight of a canister that contains fluid basedon weight information from a scale; detecting, by the one or moreprocessors, a change in the weight of the canister that contains thefluid; causing, by the one or more processors, an imaging device tocapture an image of the fluid in the canister in response to the changein the weight of the canister; providing, by the one or more processors,an estimated volume of the fluid in the canister based on the imagecaused to be captured in response to the change in the weight of thecanister; determining, by the one or more processors, a hemoglobin valueof the fluid in the canister based on the image of the fluid; andmodifying, by the one or more processors, the hemoglobin value of thefluid.
 27. Apparatus comprising: a canister receptacle to receive acanister, the canister to receive fluid from a patient; a weightmeasurement element arranged to measure weight of the canister includingthe fluid; an image capture device to capture of an image of the fluid,the capture device being triggered based on weight information from theweight measurement element; and a communication interface to communicatethe weight information and image data to a processing unit that triggersthe image capture device, the processing unit being configured toinitiate a draining of the fluid from the canister, and to set areference weight of the canister in response to completion of theinitiated draining of the fluid.
 28. A system comprising: a canister; ascale; an imaging device; and a processor configured to cause theimaging device to capture an image of fluid in the canister based onweight information from the scale, the processor being furtherconfigured to initiate a draining of the fluid from the canister, and toset a reference weight of the canister in response to completion of theinitiated draining of the fluid.
 29. A method comprising: monitoring, byone or more processors, a weight of a canister that contains fluid basedon weight information from a scale; detecting, by the one or moreprocessors, a change in the weight of the canister that contains thefluid; causing, by the one or more processors, an imaging device tocapture an image of the fluid in the canister in response to the changein the weight of the canister; providing, by the one or more processors,an estimated volume of the fluid in the canister based on the imagecaused to be captured in response to the change in the weight of thecanister; initiating, by the one or more processors, a draining of thefluid from the canister; and setting, by the one or more processors, areference weight of the canister in response to completion of theinitiated draining of the fluid.
 30. Apparatus comprising: a canisterreceptacle to receive a canister, the canister to receive fluid from apatient; a weight measurement element arranged to measure weight of thecanister including the fluid; an image capture device to capture of animage of the fluid, the capture device being triggered based on weightinformation from the weight measurement element; and a communicationinterface to communicate the weight information and image data to aprocessing unit that triggers the image capture device, the processingunit being configured to detect removal of the canister from a canisterreceptacle based on the weight information, and to store at least one ofa fluid concentration value of the fluid in the canister or a fluidvolume value of the fluid in the canister in response to the detectedremoval of the canister.
 31. A system comprising: a canister; a scale;an imaging device; and a processor configured to cause the imagingdevice to capture an image of fluid in the canister based on weightinformation from the scale, the processor being further configured todetect removal of the canister from a canister receptacle based on theweight information, and to store at least one of a fluid concentrationvalue of the fluid in the canister or a fluid volume value of the fluidin the canister in response to the detected removal of the canister. 32.A method comprising: monitoring, by one or more processors, a weight ofa canister that contains fluid based on weight information from a scale;detecting, by the one or more processors, a change in the weight of thecanister that contains the fluid; causing, by the one or moreprocessors, an imaging device to capture an image of the fluid in thecanister in response to the change in the weight of the canister;providing, by the one or more processors, an estimated volume of thefluid in the canister based on the image caused to be captured inresponse to the change in the weight of the canister; detecting, by theone or more processors, removal of the canister from a canisterreceptacle based on the weight information; and storing, by the one ormore processors, at least one of a fluid concentration value of thefluid in the canister or a fluid volume value of the fluid in thecanister in response to the detected removal of the canister. 33.Apparatus comprising: a canister receptacle to receive a canister, thecanister to receive fluid from a patient; a weight measurement elementarranged to measure weight of the canister including the fluid; an imagecapture device to capture of an image of the fluid, the capture devicebeing triggered based on weight information from the weight measurementelement; and a communication interface to communicate the weightinformation and image data to a processing unit that triggers the imagecapture device, the processing unit being configured to detect removalof the canister from the canister receptacle based on the weightinformation, and to reset at least one of a counter corresponding to thefluid or a register corresponding to the fluid in response to thedetected removal of the canister.
 34. A system comprising: a canister; ascale; an imaging device; and a processor configured to cause theimaging device to capture an image of fluid in the canister based onweight information from the scale, the processor being furtherconfigured to detect removal of the canister from a canister receptaclebased on the weight information, and to reset at least one of a countercorresponding to the fluid or a register corresponding to the fluid inresponse to the detected removal of the canister.
 35. A methodcomprising: monitoring, by one or more processors, a weight of acanister that contains fluid based on weight information from a scale;detecting, by the one or more processors, a change in the weight of thecanister that contains the fluid; causing, by the one or moreprocessors, an imaging device to capture an image of the fluid in thecanister in response to the change in the weight of the canister;providing, by the one or more processors, an estimated volume of thefluid in the canister based on the image caused to be captured inresponse to the change in the weight of the canister; detecting, by theone or more processors, removal of the canister from a canisterreceptacle based on the weight information; and resetting, by the one ormore processors, at least one of a counter corresponding to the fluid ora register corresponding to the fluid in response to the detectedremoval of the canister.
 36. Apparatus comprising: a canister receptacleto receive a canister, the canister to receive fluid from a patient; aweight measurement element arranged to measure weight of the canisterincluding the fluid; an image capture device to capture of an image ofthe fluid, the capture device being triggered based on weightinformation from the weight measurement element; and a communicationinterface to communicate the weight information and image data to aprocessing unit that triggers the image capture device, the processingunit being configured to transform at least one of absolute color valuesin the image or color gradients across pixels in the image into aquantitative estimation of a concentration of a blood component in thefluid.
 37. A system comprising: a canister; a scale; an imaging device;and a processor configured to cause the imaging device to capture animage of fluid in the canister based on weight information from thescale, the processor being further configured to transform at least oneof absolute color values in the image or color gradients across pixelsin the image into a quantitative estimation of a concentration of ablood component in the fluid.
 38. A method comprising: monitoring, byone or more processors, a weight of a canister that contains fluid basedon weight information from a scale; detecting, by the one or moreprocessors, a change in the weight of the canister that contains thefluid; causing, by the one or more processors, an imaging device tocapture an image of the fluid in the canister in response to the changein the weight of the canister; providing, by the one or more processors,an estimated volume of the fluid in the canister based on the imagecaused to be captured in response to the change in the weight of thecanister; and transforming, by the one or more processors, at least oneof absolute color values in the image or color gradients across pixelsin the image into a quantitative estimation of a concentration of ablood component in the fluid.
 39. Apparatus comprising: a canisterreceptacle to receive a canister, the canister to receive fluid from apatient; a weight measurement element arranged to measure weight of thecanister including the fluid; an image capture device to capture of animage of the fluid, the capture device being triggered based on weightinformation from the weight measurement element; and a communicationinterface to communicate the weight information and image data to aprocessing unit that triggers the image capture device, the processingunit being configured to estimate a concentration of a blood componentin the fluid based on the weight.
 40. A system comprising: a canister; ascale; an imaging device; and a processor configured to cause theimaging device to capture an image of fluid in the canister based onweight information from the scale, the processor being furtherconfigured to estimate a concentration of a blood component in the fluidbased on the weight.
 41. A method comprising: monitoring, by one or moreprocessors, a weight of a canister that contains fluid based on weightinformation from a scale; detecting, by the one or more processors, achange in the weight of the canister that contains the fluid; causing,by the one or more processors, an imaging device to capture an image ofthe fluid in the canister in response to the change in the weight of thecanister; providing, by the one or more processors, an estimated volumeof the fluid in the canister based on the image caused to be captured inresponse to the change in the weight of the canister; and estimating, bythe one or more processors, a concentration of a blood component in thefluid based on the weight.